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Thread: K40 troubleshooting, fixed, runs great now thanks

  1. #21
    Join Date
    Apr 2013
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    NE Ohio
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    I think I got it. I never even noticed that area before as it never presented a problem. Sure - I think you could soften those edges a little but I'd start with the sandpaper first and maybe some emery cloth? It really shouldn't take much. You probably want to protect the integrity of those curves so a stone with a straight edge might be a problem. But I think I see what you mean. I think mine is just softened with 15 years of wear
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  2. #22
    Join Date
    Dec 2013
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    Spokane, Washington
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    Yes, that is the culprit, that edge rests right on my thumb knuckle.

    I was going to borrow a round machinists stone, if you say sandpaper will work I will start with that. I assumed the stainless was too hard to sand.

    Thanks for the input.

  3. #23
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    Give the sandpaper a try. You can always upgrade to the stone. Whatever you think will take the least material is what I'd start with.

    Some here who've done "melt" jobs may have some good input.
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  4. #24
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    Oct 2010
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    North Central Florida
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    Sandpaper will be more controllable on an irregular shape like that. Depending on the amount you want to remove, I would start with 220 and progress to 400 with one or to steps between. Try to keep your removal to the very edges, because if/when you hit the back flatter area you will change the sheen.

    I would put some masking tape, or electricians tape on the flats that you don't want to change. Finish the edges off with a gray scotch brite pad and you should be pretty happy with the result.

  5. #25
    Join Date
    Dec 2013
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    Spokane, Washington
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    Quote Originally Posted by FLBri View Post
    Sandpaper will be more controllable on an irregular shape like that. Depending on the amount you want to remove, I would start with 220 and progress to 400 with one or to steps between. Try to keep your removal to the very edges, because if/when you hit the back flatter area you will change the sheen.

    I would put some masking tape, or electricians tape on the flats that you don't want to change. Finish the edges off with a gray scotch brite pad and you should be pretty happy with the result.

    Great advice, Thank you.

  6. #26
    Join Date
    Dec 2013
    Location
    Spokane, Washington
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    The stainless K40 performance has improved. I have been tuning and polishing parts in an attempt to resolve a coulple of issues.

    During the last 50 round test fire:

    One jam, the round became wedged between the feed ramp and the breech face with the rear of the case tilted upward.

    (I have polished the feed ramp)

    Three or four return to battery without stripping a round.

    (Removed the magazine catch and polished the bevel, sanded and polished the magazine followers so they pass the mag catch smooth when a disassembled mag is inserted in the mag well.)

    Three or four premature slide lock.

    (Sanded and polished the slide stop lever so rounds rising in the magazine are less likely to bump it and engage the lock.)

    New springs are on order. I will let you know how the next fifty rounds goes. I wont give up on this Kahr as I love it so. I am commited to seeing it through until it is dependable. Thank you all for your advice and input.

  7. #27
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    Dec 2013
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    Spokane, Washington
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    Shot another 50 rounds after sanding and polishing feed ramp, mag followers and internal slide stop lever. Experienced less malfunctions. I am starting to think the gun doesnt like the shape of the bullet on my duty ammo.

    Had one slide lock with rounds in the magazine.

    Two rounds wedged between feed ramp and breech face.

    One round jammed between the top of the barrel and the breech face.

    One incident of going full into battery without stripping a round.
    (Not sure what is causing this or how to fix it)

    One fail to lock back on empty magazine. (probably because of my slide stop modification) Will attempt to post pictures from photobucket.

    I will try to find some ammo with a bullet that is not as blunt as this Federal 180 JHP and see how it performs. Sure would like to shoot this round as I have better access to it.

    This is the ammo I am breaking the pistol in with and the ammo I would like to use for every day carry.



    Last edited by AFCop; 04-10-2014 at 06:10 AM.

  8. #28
    Join Date
    Dec 2013
    Location
    Spokane, Washington
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    It running good now.

    Replaced the slide stop with a free factory provided new slide stop.

    Replaced the recoil spring and the magazine springs.

    No jams, no premature slide lock, no failure to strip a round.

    All of the problems were solved with new springs. The new magazine springs were about three times as long as the old (set) mag springs. I broke a sweat trying to cram all that coiled steel into those little mags.

    I think the weak mag springs were allowing the rounds inside the mag to ride forward and engage the slide lock lever on thier way up.

    Thanks for all your help.

    So all is well, I have been meaning to ask you other K40 owners. Does your slide stop hole have a notch cut in the top near the slide stop spring inside the frame like this?


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